Lubricating pumps are known which feed a number of jets of pressurized lubricating fluid to a lubricated member, e.g. a drive or turbine, and recover the lubricating fluid from the casing housing the member.
More specifically, lubricating pumps of this sort comprise a first or delivery stage, and a second or recovery stage.
The delivery stage comprises an intake connected hydraulically to a lubricating fluid tank; and a delivery outlet connected hydraulically to a number of nozzles for emitting respective jets of pressurized lubricating fluid onto the lubricated member.
The delivery stage thus ensures the nozzles are fed constantly with pressurized lubricating fluid for supply to the lubricated member.
The recovery stage comprises an inlet connected hydraulically to an opening in the casing of the lubricated member; and an outlet connected hydraulically to the tank.
More specifically, the opening is formed in the base of the casing housing the lubricated member.
After lubricating the member, the lubricating fluid is thus drawn off from the base by the recovery stage and fed back to the tank.
A need is felt to prevent lubricating fluid from accumulating or settling around the opening in the base, and to ensure effective lubrication of the member, while at the same time reducing as far as possible the number of mechanical parts, weight, and size of the lubricating pump itself.
This is particularly so in the case of aircraft applications, in which any reduction in weight reduces the power and fuel requirements of the aircraft.